function [Cd0] = calc_Cd0_aircraft(aircraft,alt,tas)

flight_cond = fill_f_cond(alt,tas,aircraft.geo.wing.mgc);

flap.ext = 0;
cd_0_wing  = cd_0_lift_surf(aircraft.geo.wing, flight_cond, 1, flap, aircraft.geo.fus.lenght, aircraft.geo.wing.S);
cd_0_vtail = cd_0_lift_surf(aircraft.geo.vtail, flight_cond, 0, flap, aircraft.geo.fus.lenght, aircraft.geo.wing.S);
cd_0_htail = cd_0_lift_surf(aircraft.geo.htail, flight_cond, 0, flap, aircraft.geo.fus.lenght, aircraft.geo.wing.S);
cd_0_fus   = body_drag(aircraft.geo.fus, flight_cond,aircraft.geo.wing.S);
cd_0_eng   = body_drag(aircraft.geo.eng, flight_cond,aircraft.geo.wing.S);

Cd0 = cd_0_wing + cd_0_vtail + cd_0_htail + cd_0_fus + cd_0_eng*aircraft.eng.number;